Abstract: Disclosed is an Air Handling Unit, AHU, including a fan inducing a flow in an air ventilation ducting system. The fan includes a front disc, a back plate and fan blades manufactured as separate units. The fan provides a radial or mixed flow. The fan blades have an upper edge including upper attachment protrusions attached to the front disc and a lower edge including lower attachment protrusions attached to the back plate. The fan blade includes at least two upper and lower attachment protrusions protruding through the front disc and back plate indentations, respectively, forming axial retainers. An axial locker on the protruding portion provides a retaining axial force between the front disc and the back plate. The fan further includes another other upper and lower attachment protrusion cooperating with front disc and back plate indentations, respectively, forming radial retainers preventing the blades from dislocating in the radial direction.

Abstract: An AHU includes air channels. The air channel includes an air inlet and outlet guiding supply air into a building from outside or extract air from a building to the outside. The AHU is connected to an air ventilation ducting system. The AHU further includes a fan inducing a flow in the system when connected thereto. The fan provides a radial flow or mixed flow. The flow from the fan is redirected from radial flow to axial flow on its way from the inlet to the outlet. To provide a more efficient flow when the air flow from the fan changes direction, the fan includes a stator ring. The stator ring has an inner circumference encircling the fan's back plate and a surface essentially levelled with the surface at the edge of the back plate. The AHU may also include a flow guiding body guiding the air further downstream.

Abstract: Disclosed is an Air Handling Unit, AHU, including a fan inducing a flow in an air ventilation ducting system. The fan includes a front disc, a back plate and fan blades manufactured as separate units. The fan provides a radial or mixed flow. The fan blades have an upper edge including upper attachment protrusions attached to the front disc and a lower edge including lower attachment protrusions attached to the back plate. The fan blade includes at least two upper and lower attachment protrusions protruding through the front disc and back plate indentations, respectively, forming axial retainers. An axial locker on the protruding portion provides a retaining axial force between the front disc and the back plate. The fan further includes another other upper and lower attachment protrusion cooperating with front disc and back plate indentations, respectively, forming radial retainers preventing the blades from dislocating in the radial direction.